The currently unnamed Mars 2020 mission was announced by NASA on 4 December 2012 at the fall meeting of the American Geophysical Union in San Francisco.[12] The rover's design is derived from the Curiosity rover, and will use many components already fabricated and tested, including different scientific instruments and a core drill.[13]

NASA announced in June 2019 that a student naming contest will be held in fall of 2019 to determine the name of the rover.[14]

The Science Definition Team proposed that the rover collect and package as many as 31 samples of rock cores and surface soil for a later mission to bring back for definitive analysis on Earth. In 2015 they expanded the concept, planning to collect even more samples and distribute the tubes in small piles or caches across the surface of Mars.[18]

In September 2013 NASA launched an Announcement of Opportunity for researchers to propose and develop the instruments needed, including the Sample Caching System.[19][20] The science instruments for the mission were selected in July 2014 after an open competition based on the scientific objectives set one year earlier.[21][22] The science conducted by the rover's instruments will provide the context needed for detailed analyses of the returned samples.[23] The chairman of the Science Definition Team stated that NASA does not presume that life ever existed on Mars, but given the recent Curiosity rover findings, past Martian life seems possible.[23]

The Mars 2020 rover will explore a site likely to have been habitable. It will seek signs of past life, set aside a returnable cache with the most compelling rock core and soil samples, and demonstrate technology needed for the future human and robotic exploration of Mars.

A key mission requirement is that it must help prepare NASA for its long-term Mars sample-return mission and crewed mission efforts.[9][10][11] The rover will make measurements and technology demonstrations to help designers of a future human expedition understand any hazards posed by Martian dust, and will test technology to produce a small amount of pure oxygen (O2) from Martian atmospheric carbon dioxide (CO2).[24] Improved precision landing technology that enhances the scientific value of robotic missions also will be critical for eventual human exploration on the surface.[25] Based on input from the Science Definition Team, NASA defined the final objectives for the 2020 rover. Those become the basis for soliciting proposals to provide instruments for the rover's science payload in the spring of 2014.[24]

The mission will also attempt to identify subsurface water, improve landing techniques, and characterize weather, dust, and other potential environmental conditions that could affect future astronauts living and working on Mars.[26]

The three major components of the Mars 2020 spacecraft are the cruise stage for travel between Earth and Mars; the Entry, Descent, and Landing System (EDLS) that includes the aeroshell, parachute, descent vehicle, and sky crane; and the rover.

The rover is based on the design of Curiosity.[12] While there are differences in scientific instruments and the engineering required to support them, the entire landing system (including the sky crane and heat shield) and rover chassis can essentially be recreated without any additional engineering or research. This reduces overall technical risk for the mission, while saving funds and time on development.[27] One of the upgrades is a guidance and control technique called "Terrain Relative Navigation" (TRN) to fine-tune steering in the final moments of landing.[28][29]

In October 2016, NASA reported using the Xombie rocket to test the Lander Vision System (LVS), as part of the Autonomous Descent and Ascent Powered-flight Testbed (ADAPT) experimental technologies, for the Mars 2020 mission landing, meant to increase the landing accuracy and avoid obstacle hazards.[30][31]
A Multi-Mission Radioisotope Thermoelectric Generator (MMRTG), left over as a backup part for Curiosity during its construction, will power the rover.[12][32]

The generator has a mass of 45 kilograms (99 lb) and uses 4.8 kilograms (11 lb) of plutonium dioxide as the source of steady supply of heat that is converted to electricity.[3] The electrical power generated is approximately 110 watts at launch with little decrease over the mission time.[3] Two lithium-ion rechargeable batteries are included to meet peak demands of rover activities when the demand temporarily exceeds the MMRTG's steady electrical output levels. The MMRTG offers a 14-year operational lifetime, and it was provided to NASA by the US Department of Energy.[3] Unlike solar panels, the MMRTG provides engineers with significant flexibility in operating the rover's instruments even at night and during dust storms, and through the winter season.[3]

Engineers redesigned the Mars 2020 rover wheels to be more robust than Curiosity's wheels, which have sustained some damage.[33] The rover will have thicker, more durable aluminum wheels, with reduced width and a greater diameter (52.5 cm, 20.7 in) than Curiosity's 50 cm (20 in) wheels.[34][35] The aluminum wheels are covered with cleats for traction and curved titanium spokes for springy support.[36] The combination of the larger instrument suite, new Sampling and Caching System, and modified wheels makes Mars 2020 heavier than its predecessor, Curiosity,[35] by 17% (1050 kg to 899 kg).

The rover will include a five-jointed robotic arm measuring 7 feet (2.1 m) long. The arm will be used in combination with a turret to analyze geologic samples from the Martian surface.[37]

The rover mission and launch are estimated to cost about US$2.1 billion.[38] The mission's predecessor, the Mars Science Laboratory, cost US$2.5 billion in total.[12] The availability of spare parts make the new rover somewhat more affordable. Curiosity's engineering team are also involved in the rover's design.[12][39]

Mars Oxygen ISRU Experiment (MOXIE), an exploration technology investigation that will produce a small amount of oxygen (O2) from Martian atmospheric carbon dioxide (CO2).[49] This technology could be scaled up in the future for human life support or to make the rocket fuel for return missions.[50]

SuperCam, an instrument suite that can provide imaging, chemical composition analysis and mineralogy in rocks and regolith from a distance. It is an upgraded version of the ChemCam on the Curiosity rover but with two lasers and four spectrometers that will allow it to remotely identify biosignatures and assess the past habitability.[51]

Mars Helicopter Scout (MHS) is a planned solar powered helicopter drone with a mass of 1.8 kg (4.0 lb) that will be tested for flight stability, and for its potential to scout the best driving route for the rover.[54] Other than cameras, it carries no scientific instruments. Its job is merely to demonstrate the practicality of flight on Mars.[55] The small helicopter is expected to fly up to five times during its 30-day testing, and will fly no more than 3 minutes per day. It is a technology demonstrator that will form the foundation on which more capable helicopters can be developed for aerial exploration of Mars and other planetary targets with an atmosphere.[56][57]

Microphones will be used during the landing event, while driving, and when collecting samples.[58]

A workshop was held on 8–10 February 2017 in Pasadena, California, to discuss these sites, with the goal of narrowing down the list to three sites for further consideration.[63] The three sites were:[64]

Jezero crater was selected in November 2018, mostly because it was a 250 m (820 ft) deep lake about 3.9 billion to 3.5 billion years ago, and it features a prominent river delta where water flowing through it deposited lots of sediment over the eons, which is "extremely good at preserving biosignatures".[6][7]

A key mission requirement for this rover is that it must help prepare NASA for its Mars sample-return mission (MSR) campaign,[38][67][68] which is needed before any crewed mission takes place.[9][10][11] Such effort would require three additional vehicles: an orbiter, a fetch rover, and a Mars ascent vehicle (MAV).

Dozens of samples would be collected and cached by the Mars 2020 rover, and would be left on the surface of Mars for possible later retrieval.[68] A "fetch rover" would retrieve the sample caches and deliver them to a Mars ascent vehicle (MAV). In July 2018 NASA contracted Airbus to produce a "fetch rover" concept.[69] The MAV would launch from Mars and enter a 500 km orbit and rendezvous with a new Mars orbiter.[68] The sample container would be transferred to an Earth entry vehicle (EEV) which would bring it to Earth, enter the atmosphere under a parachute and hard-land for retrieval and analyses in specially designed safe laboratories.[67][68]

The mission has a current launch window of 17 July to 5 August 2020, where the positions of Earth and Mars are optimal for traveling to Mars. The rover is scheduled to land on Mars on 18 February 2021, with a planned surface mission of at least 1 Mars year (668 sols or 687 Earth days).[4]

^ abcdefHarwood, William (4 December 2012). "NASA announces plans for new $1.5 billion Mars rover". CNET. Retrieved 5 December 2012. Using spare parts and mission plans developed for NASA's Curiosity Mars rover, Ronnie Pickering says it can launch the rover in 2020 and stay within current budget guidelines.

^"Mars 2020 Rover's 7-Foot-Long Robotic Arm Installed". mars.nasa.gov. 28 June 2019. Retrieved 1 July 2019. The main arm includes five electrical motors and five joints (known as the shoulder azimuth joint, shoulder elevation joint, elbow joint, wrist joint and turret joint). Measuring 7 feet (2.1 meters) long, the arm will allow the rover to work as a human geologist would: by holding and using science tools with its turret, which is essentially its "hand."